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Der Aufsatz schlägt die Verbindung und Erweiterung von Analysen des (neoliberalen) Regierens mit nicht-subjektzentrierten und affekttheoretischen Ansätzen vor. Anhand einer Analyse des sozialpolitischen und sozialarbeiterischen Umgangs mit Wohnungslosen wird nachvollzogen, welcher Gewinn sich aus der Verbindung von gouvernementalen und affekttheoretischen Perspektiven ergeben kann. Aus einer gouvernementalen Perspektive wird zunächst nachgezeichnet, wie Affekte und Emotionen in Räumen des betreuten Wohnens für Wohnungslose zum Gegenstand fürsorglicher Intervention werden. Im betreuten Wohnen kommen Mikrotechniken zum Einsatz, die auf eine "ausgewogene" emotionale Bindung an Wohnräume und ihr Inventar hinarbeiten. Das betreute Wohnen ist von Problematisierungen durchzogen, die Wohnungslosigkeit als emotionale Haltung der Rastlosigkeit und Unruhe, als einen Mangel an Verbundenheit mit Orten und Dingen deuten. Gleichzeitig wird den Untergebrachten häufig auch eine übersteigerte affektive Bindung an Dinge unterstellt, die sogenannte "Horder" und "Messies" an einer sozial unauffälligen Haushaltsführung hindere. Eine gouvernementale Analyse kann die therapeutische Rationalität sichtbar machen, die diesen Problematisierungen zugrunde liegt. Eine gouvernementale Analyse allein bietet gleichwohl keine Möglichkeit, alternative Erzählungen über die Bedeutung affektiver Beziehungen für das Wohnen zu entwickeln. Mithilfe unterschiedlicher affekttheoretischer Ansätze geht der Aufsatz daher auch der Frage nach, wie sich jenseits therapeutisierender Perspektiven über das Wohnen und die Bedeutung von Bindungen an Orte und Dinge nachdenken lässt. Nicht-subjektzentrierte Konzepte von Affektivität ermöglichen solche alternativen Erzählungen und eröffnen neue Fluchtlinien der Kritik: Wohnen wir sichtbar als immer schon "betreut", eingelassen in ein Netz von intersubjektiven und interobjektiven Beziehungen.
Reconstructions of biomass burning from sediment charcoal records to improve data–model comparisons
(2015)
The location, timing, spatial extent, and frequency of wildfires are changing rapidly in many parts of the world, producing substantial impacts on ecosystems, people, and potentially climate. Paleofire records based on charcoal accumulation in sediments enable modern changes in biomass burning to be considered in their long-term context. Paleofire records also provide insights into the causes and impacts of past wildfires and emissions when analyzed in conjunction with other paleoenvironmental data and with fire models. Here we present new 1000-year and 22 000-year trends and gridded biomass burning reconstructions based on the Global Charcoal Database version 3 (GCDv3), which includes 736 charcoal records (57 more than in version 2). The new gridded reconstructions reveal the spatial patterns underlying the temporal trends in the data, allowing insights into likely controls on biomass burning at regional to global scales. In the most recent few decades, biomass burning has sharply increased in both hemispheres but especially in the north, where charcoal fluxes are now higher than at any other time during the past 22 000 years. We also discuss methodological issues relevant to data–model comparisons and identify areas for future research. Spatially gridded versions of the global data set from GCDv3 are provided to facilitate comparison with and validation of global fire simulations.
Die Sulfonyl-Gruppe (-SO2-) ist ein weit verbreitetes Strukturmotiv in der organischen Chemie und Bestandteil vieler biologisch aktiver Moleküle, insbesondere Arzneistoffen. Zwei der am häufigsten auftretenden Gruppen sind Sulfone und Sulfonamide, die in über 100 zugelassenen Medikamenten und 10% der meistverkauften Medikamente sind. Insofern kommt der Entwicklung neuer Synthesemethoden eine große Bedeutung zu. Dabei stehen besonders einfache, wirtschaftliche und zeitsparende Vorgehensweisen im Vordergrund, die eine große Bandbreite an neuen Substanzen generieren können. Ein Ansatz hierfür sind Multikomponenten- oder Eintopfreaktionen.
Aufgrund der Wichtigkeit dieser zwei Strukturklassen, sollen im Rahmen der hier vorliegenden Doktorarbeit neue Syntheserouten für Sulfone und Sulfonamide entwickelt werden. Besonderes Augenmerk wird auf die die Einführung der SO2-Einheit während der Reaktionsführung gelegt. Im Vergleich zu bereits existierenden Verfahren ist dies ein enormer Fortschritt, da die Mehrheit der bekannten Routen auf Schwefel- oder Schwefeldioxid-haltige Startmaterialien zurückgreift.
In der vorliegenden Arbeit gelang es, einen synthetischen Zugang zu Arylsulfonen basierend auf von Natrium-, Lithium-, Magnesium- und Zinksulfinaten zu finden. Diese Reaktion besitzt eine sehr große Anwendungsbandbreite und setzt sowohl Aryl- als auch Alkylsulfinate effizient um. Außerdem weisen Reaktionen mit unsymmetrischen Diaryliodoniumsalzen hohe Chemoselektivitäten auf.
Auf der Grundlage auf der Reaktion zwischen Natriumsulfinaten und Iodoniumsalzen wurde eine simple Route zur Synthese von Diarylsulfonen abgeleitet, jedoch war hierbei die Sulfonylgruppe noch Bestandteil eines der Edukte. Um die SO2-Einheit während der Reaktion einführen zu können, wurde ein praktisches Eintopf-Protokoll entwickelt, welches die direkte Umsetzung von (hetero)aromatischen und alkylischen Halogeniden zu Arylsulfonen gestattet. Diese innovative Methode besteht aus folgenden vier Schritten: (1) Generierung des Organometallreagenzes via Halogen-Metall-Austausch, direkte Metallinsertion oder Deprotonierung; (2) Reaktion des Organometallreagenzes mit SO2 zum Sulfinat; (3) Entfernen des SO2-Überschusses und flüchtiger Komponenten und (4) Umsetzung des nicht aufgereinigten Sulfinates mit einem Iodoniumsalz.
Desweiteren wird in dieser Arbeit ein neuartiger Übergangsmetall-katalysierter Ansatz zur Darstellung von Diarylsulfonen ausgehend von Arylhalogeniden und Sulfinaten diskutiert. Erste Experimente deuten auf Nickel-Katalysatoren als gute Wahl für die Reaktion. Optimierungsreaktionen zeigten eine starke Abhängigkeit der Ausbeute in Hinsicht auf die Bisswinkel der an das zentrale Nickelatom koordinierten Liganden. Da die bis dato besten Ergebnisse mit dem Komplex [o-tol-Ni(PPh2Me)2Cl] erzielt wurden, wird der [o-tol-Ni(PMe3)2Cl]-Komplex momentan in unserem Labor weiteren Studien unterzogen. Bislang ist davon auszugehen, dass dieser Katalysator hervorragende Ergebnisse liefert und zu einer allgemein gültigen Methode führt.
In weiteren Kapiteln wird die Anwendbarkeit von SO2-Surrogaten, Metabisulfiten „S2O52-„ oder DABSO; untersucht; mit dem Ziel eine Eintopf- oder Multikomponentenreaktion zu entwickeln.
Zum einen wird die Entwicklung einer Ein-Topf-Reaktion von Alkylhalogeniden mit Metabisulfiten und Organozinkreagenzien zur Darstellung von Alkylarylsulfonen vorgestellt. Darüber hinaus wird eine Übergangsmetall-katalysierte Multikomponenten Reaktion zur Synthese von Sulfonsäureamiden vorgestellt. Eine Reaktion zwischen Aminen, Arylhalogeniden und DABSO als SO2-Quelle wurde in Form einer Palladium-katalysierten Aminosulfonylierung entwickelt.
Asymmetric conflicts in which rule is contested by non-state actors are often interpreted as a destabilization of order. This also holds true for the case of IS. Indeed, it cannot be denied that its transnational “jihad” has contributed to destabilizing a whole region. On the other hand, it has been repeatedly noted that IS has – within the territory it controls – established an alternative order offering stability. At least for those who fit in the worldview of the wannabe-caliphate. As reported by inhabitants of its powerhouse Raqqa, IS does not only create obedience by force but also by providing administration, workplaces and public services. Or as Benham T. Said put it, some few Arabs “associate an Islamic state with notions of justice, stability and prosperity”...
Detectors of modern high-energy physics experiments generate huge data rates during operation. The efficient read-out of this data from the front-end electronics is a sophisticated task, the main challenges, however, may vary from experiment to experiment. The Compressed Baryonic Matter (CBM) experiment that is currently under construction at the Facility for Antiproton and Ion Research (FAIR) in Darmstadt/Germany foresees a novel approach for data acquisition.
Unlike previous comparable experiments that organize data read-out based on global, hierarchical trigger decisions, CBM is based on free-running and self-triggered front-end electronics. Data is pushed to the next stage of the read-out chain rather than pulled from the buffers of the previous stage. This new paradigm requires a completely new development of read-out electronics.
As one part of this thesis, a firmware for a read-out controller to interface such a free-running and self-triggered front-end ASIC, the GET4 chip, was implemented. The firmware in question was developed to run on a Field Programmable Gate Array (FPGA). An FPGA is an integrated circuit whose behavior can be reconfigured "in the field" which offers a lot of flexibility, bugs can be fixed and also completely new features can be added, even after the hardware has already been installed. Due to these general advantages, the usage of FPGAs is desired for the final experiment. However, there is also a drawback to the usage of FPGAs. The only affordable FPGAs today are based on either SRAM or Flash technology and both cannot easily be operated in a radiation environment.
SRAM-based devices suffer severely from Single Event Upsets (SEUs) and Flash-based FPGAs deteriorate too fast from Total Ionizing Dose (TID) effects.
Several radiation mitigation techniques exist for SRAM-based FPGAs, but careful evaluation for each use case is required. For CBM it is not clear if the higher resource consumption of added redundancy, that more or less directly translates in to additional cost, outweighs the advantaged of using FPGAs. In addition, it is even not clear if radiation mitigation techniques (e.g. scrubbing) that were already successfully put into operation in space applications also work as efficiently at the much higher particle rates expected at CBM.
In this thesis, existing radiation mitigation techniques have been analyzed and eligible techniques have been implemented for the above-mentioned read-out controller. To minimize additional costs, redundancy was only implemented for selected parts of the design.
Finally, the radiation mitigated read-out controller was tested by mounting the device directly into a particle beam at Forschungszentrum Jülich. The tests show that the radiation mitigation effect of the implemented techniques remains sound, even at a very high particle flux and with only part of the design protected by costly redundancy.
The promising results of the in-beam tests suggest to use FPGAs in the read-out chain of the CBM-ToF detector.
Background: Acquired resistance to standard chemotherapy causes treatment failure in patients with metastatic bladder cancer. Overexpression of pro-survival Bcl-2 family proteins has been associated with a poor chemotherapeutic response, suggesting that Bcl-2-targeted therapy may be a feasible strategy in patients with these tumors. The small-molecule pan-Bcl-2 inhibitor (−)-gossypol (AT-101) is known to induce apoptotic cell death, but can also induce autophagy through release of the pro-autophagic BH3 only protein Beclin-1 from Bcl-2. The potential therapeutic effects of (−)-gossypol in chemoresistant bladder cancer and the role of autophagy in this context are hitherto unknown.
Methods: Cisplatin (5637rCDDP1000, RT4rCDDP1000) and gemcitabine (5637rGEMCI20, RT4rGEMCI20) chemoresistant sub-lines of the chemo-sensitive bladder cancer cell lines 5637 and RT4 were established for the investigation of acquired resistance mechanisms. Cell lines carrying a stable lentiviral knockdown of the core autophagy regulator ATG5 were created from chemosensitive 5637 and chemoresistant 5637rGEMCI20 and 5637rCDDP1000 cell lines. Cell death and autophagy were quantified by FACS analysis of propidium iodide, Annexin and Lysotracker staining, as well as LC3 translocation.
Results: Here we demonstrate that (−)-gossypol induces an apoptotic type of cell death in 5637 and RT4 cells which is partially inhibited by the pan-caspase inhibitor z-VAD. Cisplatin- and gemcitabine-resistant bladder cancer cells exhibit enhanced basal and drug-induced autophagosome formation and lysosomal activity which is accompanied by an attenuated apoptotic cell death after treatment with both (−)-gossypol and ABT-737, a Bcl-2 inhibitor which spares Mcl-1, in comparison to parental cells. Knockdown of ATG5 and inhibition of autophagy by 3-MA had no discernible effect on apoptotic cell death induced by (−)-gossypol and ABT-737 in parental 5637 cells, but evoked a significant increase in early apoptosis and overall cell death in BH3 mimetic-treated 5637rGEMCI20 and 5637rCDDP1000 cells.
Conclusions: Our findings show for the first time that (−)-gossypol concomitantly triggers apoptosis and a cytoprotective type of autophagy in bladder cancer and support the notion that enhanced autophagy may underlie the chemoresistant phenotype of these tumors. Simultaneous targeting of Bcl-2 proteins and the autophagy pathway may be an efficient new strategy to overcome their "autophagy addiction" and acquired resistance to current therapy.
Members of the Sm protein family are important for the cellular RNA metabolism in all three domains of life. The family includes archaeal and eukaryotic Lsm proteins, eukaryotic Sm proteins and archaeal and bacterial Hfq proteins. While several studies concerning the bacterial and eukaryotic family members have been published, little is known about the archaeal Lsm proteins. Although structures for several archaeal Lsm proteins have been solved already more than ten years ago, we still do not know much about their biological function, however one can confidently propose that the archaeal Lsm proteins will also be involved in RNA metabolism. Therefore, we investigated this protein in the halophilic archaeon Haloferax volcanii. The Haloferax genome encodes a single Lsm protein, the lsm gene overlaps and is co-transcribed with the gene for the ribosomal L37.eR protein. Here, we show that the reading frame of the lsm gene contains a promoter which regulates expression of the overlapping rpl37R gene. This rpl37R specific promoter ensures high expression of the rpl37R gene in exponential growth phase. To investigate the biological function of the Lsm protein we generated a lsm deletion mutant that had the coding sequence for the Sm1 motif removed but still contained the internal promoter for the downstream rpl37R gene. The transcriptome of this deletion mutant was compared to the wild type transcriptome, revealing that several genes are down-regulated and many genes are up-regulated in the deletion strain. Northern blot analyses confirmed down-regulation of two genes. In addition, the deletion strain showed a gain of function in swarming, in congruence with the up-regulation of transcripts encoding proteins required for motility.
A data-driven method was applied to Au+Au collisions at √sNN = 200 GeV made with the STAR detector at RHIC to isolate pseudorapidity distance η-dependent and η-independent correlations by using two- and four-particle azimuthal cumulant measurements. We identified a η-independent component of the correlation, which is dominated by anisotropic flow and flow fluctuations. It was also found to be independent of η within the measured range of pseudorapidity |η| < 1. In 20–30% central Au+Au collisions, the relative flow fluctuation was found to be 34%±2%(stat.)±3%(sys.) for particles with transverse momentum pT less than 2 GeV/c. The η-dependent part, attributed to nonflow correlations, is found to be 5% ± 2%(sys.) relative to the flow of the measured second harmonic cumulant at |η| > 0.7.
Background. There is growing public and scientific concern about the occurrence of anthropogenic chemicals in the aquatic environment. Surface and groundwater serve as main drinking water resource. Especially in metropolitan areas these water reservoirs are impacted by organic pollutants predominantly originating from wastewater treatment plant (WWTP) effluents. The impact of wastewater derived anthropogenic chemicals is therefore related to environmental and human health concerns. In order to lower the potential environmental and human health risk from wastewater associated pollutants, strategies for enhanced pollutant removal are applicable in a medium-term perspective. Ozonation and powdered activated carbon treatment are the two advanced wastewater treatment technologies, which are technically mature as well as economically feasible for the application in large-scale wastewater treatment plants. While powdered activated carbon removes substances by adsorption, ozonation degrades a parent compound into oxidation products. Most of the available research has been done at lab-scale while onsite ecotoxicity tests and chemical analyses are rare.
Objectives. For a comparative evaluation of advanced wastewater treatments' potential to alter toxicity, a broad spectrum of ecotoxicological data need to be collected. The focus has been set on three major objectives: A) Evaluation of the endocrine activity; B) Evaluation of the unspecific toxicity; C) Evaluation of genotoxicity and mutagenicity.
Methods. The advanced treatment methods, ozonation and powdered activated carbon treatment of secondary wastewater effluents, – each equipped with subsequent sand filtration as additional post treatment step – were ecotoxico-logically characterized at a pilot-scale WWTP. For process control the elimination of 35 selected pharmaceuticals was identified by chemical analyses using HPLC-MS/MS.
The endocrine activity ((anti-)estrogenic, (anti-)androgenic, dioxin-like activity)) was characterized by yeast-based in vitro bioassays and cytotoxicity by cell based assays. Genotoxicity and mutagenicity was assessed using umuC'assay and Ames assay, respectively. All in vitro assays were performed using extracts of the wastewater samples. In vivo toxicity was assessed with the fish early life stage test with rainbow trout (Oncorhynchus mykiss). Ozonation was additionally assessed at a full-scale WWTP with in-vitro tests on endocrine activity and cytotoxicity and in vivo toxicity tests using five aquatic model organisms: Lemna minor, Daphnia magna, Chironomus riparius, Lumbriculus variegatus, Potamopyrgus antipodarum.
Results. In conventional activated sludge treated effluents the residual estrogenicity, antiandrogenicity, aryl hydrocarbon receptor agonistic activity and cytotoxicity were considerably reduced while antiestrogenicity was increased by both advanced treatment technologies. Ozonation led to an increase in genotoxic effects detected with Ames assay and with single cell gel electrophoresis of rainbow trout erythrocytes. Furthermore, mortality of rainbow trout was increased and reproduction of L. variegatus was decreased. Sand filtration lessened the genotoxic effects and adjusted reproduction of L. variegatus and mortality of rainbow trout to a similar level as conventional treatment.
Conclusions. This work demonstrates that conventional activated sludge treatment induces in vitro and in vivo toxicity. Advanced wastewater treatment combined with subsequent sand filtration can reduce in vitro and in vivo toxicity. An observed increase of endocrine activity after advanced wastewater treatment is an indication for different removal efficiencies of chemicals causing agonistic or antagonistic activity, respectively. Ozonation of wastewater generates ecotoxicity, which is largely removed by subsequent sand filtration. After a comprehensive investigation and after assurance of the removal of adverse effects, advanced treatment technologies could have beneficial effects on the ecological quality of the receiving water.
Le genre des questions-et-réponses dans la littérature grecque chrétienne se laisse mieux comprendre si l'on le définit comme une série de questions-et-réponses, présentées comme telles (et non comme des lettres ou des dialogues, par exemple) abordant des sujets variés et qui ne se réduisent pas à une seule catégorie de contenu (exégèse biblique ou explications scientifiques, par exemple). Ainsi restreint, le genre des questions-et-réponses dans la littérature grecque chrétienne connaît sa période la plus faste aux Ve-VIIIe s. dans des milieux monastiques ouverts sur les problèmes et les interrogations du monde. Ce genre, d'une grande souplesse et d'une grande vitalité, permet de traiter des questions d'une façon plus accessible et plus libre qu'il ne serait possible de le faire dans une homélie ou un traité théologique.
Repeated Quaternary glaciations have significantly shaped the present distribution and diversity of several European species in aquatic and terrestrial habitats. To study the phylogeography of freshwater invertebrates, patterns of intraspecific variation have been examined primarily using mitochondrial DNA markers that may yield results unrepresentative of the true species history. Here, population genetic parameters were inferred for a montane aquatic caddisfly, T hremma gallicum , by sequencing a 658‐bp fragment of the mitochondrial CO 1 gene, and 12,514 nuclear RAD loci. T . gallicum has a highly disjunct distribution in southern and central Europe, with known populations in the Cantabrian Mountains, Pyrenees, Massif Central, and Black Forest. Both datasets represented rangewide sampling of T. gallicum . For the CO 1 dataset, this included 352 specimens from 26 populations, and for the RAD dataset, 17 specimens from eight populations. We tested 20 competing phylogeographic scenarios using approximate Bayesian computation (ABC ) and estimated genetic diversity patterns. Support for phylogeographic scenarios and diversity estimates differed between datasets with the RAD data favouring a southern origin of extant populations and indicating the Cantabrian Mountains and Massif Central populations to represent highly diverse populations as compared with the Pyrenees and Black Forest populations. The CO 1 data supported a vicariance scenario (north–south) and yielded inconsistent diversity estimates. Permutation tests suggest that a few hundred polymorphic RAD SNP s are necessary for reliable parameter estimates. Our results highlight the potential of RAD and ABC‐based hypothesis testing to complement phylogeographic studies on non‐model species.
The stable isotope geochemistry of pedogenic and lacustrine carbonate and fossil herbivore tooth enamel is a powerful tool to study the evolution of terrestrial paleoenvironments. This thesis aims to reconstruct Neogene ecosystems in the Karonga Basin in the southern part the East African Rift (EAR) and the Central Anatolian Plateau (CAP).
Karonga Basin: Understanding the development of East African savanna biomes is crucial for reconstructing the evolution, migration and dietary behaviors of early hominins. These rift ecosystems range from closed woodland to open grassland savanna and vary widely in fraction of woody cover. Here I present Plio-Pleistocene carbon (δ13C) and oxygen (δ18O) records from pedogenic carbonate and fossil herbivore tooth enamel collected from the Malawi Rift. This is the first southern hemisphere long-term record in the East African Rift.
The studied ca. 4.3 Ma to 0.6 Ma deposits of the Chiwondo Beds (Karonga Basin) are home to two hominin fossil finds, a maxillary fragment of Paranthropus boisei and a mandible of Homo rudolfensis, both dated to ca. 2.4 Ma. The study site is situated between the well-known hominin-bearing localities of eastern and southern Africa and hence fills an important geographical gap for early hominin research.
The δ13C values of pedogenic carbonate (n = 321) and of enamel from 14 different large-bodied herbivorous mammal taxa (suid, equid, bovid, elephant an hippopotamus; n = 122) permit assessment of the evolutionary history of C3 and C4 biomass, which is closely linked to climate patterns. The reconstruction of C4-grassland development offers insights into the retreat of tree cover and the distribution and seasonality of precipitation. δ18O values reflect hydrological patterns, and we supplement the data of fossil proxy material with analyses of modern meteoric water to evaluate influences of seasonality and evaporation.
Consistent δ13C values around -9‰ and δ18O values of ca. 24‰ of the pedogenic carbonate from 14 sections spanning the last 4.3 Ma indicate a relatively mesic and persistent climate with C3-dominated woodland savannas in the Karonga Basin. The data from tooth enamel of suid, elephant, and hippo taxa complement these findings with constantly low δ13C and δ18O values, demonstrating intake of mainly C3 biomass and water from sources which are only very limited affected by evaporation.
In contrast, Karonga Basin equid and bovid taxa reflect much more complex dietary patterns, ranging from mixed C3/C4-feeders to strongly C4-influenced diets. Intra-tooth δ18O values also show large variations, indicating water intake from resources that differ in their isotopic composition and therefore experienced different hydrological settings.
Overall, the stable isotope data reflect a mostly C3-dominated mesic paleoecosystem, which comprises patches of more open C4-grasslands within the range of migrating mammals. Supplementary analyses of δ18O values of modern meteoric water (precipitation, lake, river and groundwater; n = 111) show a similar magnitude to the fossil herbivore oxygen isotopic values. Expected 18O values of the drinking water calculated from herbivore enamel of animals with a mixed- or C3-diet indicate water intake from barely evaporated sources. Specialized feeders with a high C4-consumtion, however, reflect s|||||||||||||||||||||values of 16O-depleted reservoirs, similar in δ18O |||||||||||| to modern evaporated lakes.
The absence of long-term trends towards more positive δ13C and δ18O values in the Karonga Basin contrasts the increasing role of C4-grasslands since ca. 2.5 Ma in the Eastern Rift. Our data hence point to regional differences in climate and vegetation dynamics during the Plio-Pleistocene. Therefore, regions that are home to early hominins such as H. rudolfensis and P. boisei may have had a different environmental history when compared to the Eastern Rift. This suggests that hominin adaptation is not necessarily directly linked to the emergence of open landscapes.
Central Anatolian Plateau: The development of relief and climate patterns in the Central Anatolian Plateau is long-standing debate in modern paleoecological studies. This thesis presents long-term δ13C and δ18O records on five lacustrine successions, which are widely distributed across the CAP. Also, new 40Ar/39Ar geochronological data from volcanic ashes are established in addition to existing biostratigraphic and paleomagnetic data.
Field relationships combined with stable isotope data of 230 lacustrine carbonates indicate a Late Oligocene environment that was characterized by large, temporally open freshwater lakes in a relatively humid subtropic climate. In the middle Aquitanian, an increase in lake δ18O values reflects more arid settings and an overall increasing dominance of closed saline lakes. This time was probably characterized by frequent climatic fluctuations, recording the influence of seasonality, topography and the waxing and waning of aridity.
Background: It is assumed that different pain phenotypes are based on varying molecular pathomechanisms. Distinct ion channels seem to be associated with the perception of cold pain, in particular TRPM8 and TRPA1 have been highlighted previously. The present study analyzed the distribution of cold pain thresholds with focus at describing the multimodality based on the hypothesis that it reflects a contribution of distinct ion channels.
Methods: Cold pain thresholds (CPT) were available from 329 healthy volunteers (aged 18 - 37 years; 159 men) enrolled in previous studies. The distribution of the pooled and log-transformed threshold data was described using a kernel density estimation (Pareto Density Estimation (PDE)) and subsequently, the log data was modeled as a mixture of Gaussian distributions using the expectation maximization (EM) algorithm to optimize the fit.
Results: CPTs were clearly multi-modally distributed. Fitting a Gaussian Mixture Model (GMM) to the log-transformed threshold data revealed that the best fit is obtained when applying a three-model distribution pattern. The modes of the identified three Gaussian distributions, retransformed from the log domain to the mean stimulation temperatures at which the subjects had indicated pain thresholds, were obtained at 23.7 °C, 13.2 °C and 1.5 °C for Gaussian #1, #2 and #3, respectively.
Conclusions: The localization of the first and second Gaussians was interpreted as reflecting the contribution of two different cold sensors. From the calculated localization of the modes of the first two Gaussians, the hypothesis of an involvement of TRPM8, sensing temperatures from 25 - 24 °C, and TRPA1, sensing cold from 17 °C can be derived. In that case, subjects belonging to either Gaussian would possess a dominance of the one or the other receptor at the skin area where the cold stimuli had been applied. The findings therefore support a suitability of complex analytical approaches to detect mechanistically determined patterns from pain phenotype data.
Ausländische Pflegekräfte in deutschen Privathaushalten : ein Interview mit Prof. Dr. Helma Lutz
(2015)
Helma Lutz ist Professorin am Fachbereich Gesellschaftswissenschaften der Goethe-Universität Frankfurt am Main. Seit 15 Jahren beschäftigt sie sich in ihrer Forschung mit "neuen Dienstmädchen" – Migrantinnen, die Haus-, Erziehungs- und Versorgungsarbeit ("Care-Arbeit") in deutschen Haushalten verrichten. Die Redaktion von focus Migration hat sie zu diesem Thema befragt.
Linking mathematics with reality is not new. It is also not new to use outdoor activities to learn mathematics. It seems to be new, to combine such mathematical outdoor activities with mobile technology, like the geocache community which makes use of GPS technology to guide their members to special places and points of interest. The use of mobile technologies to learn at any time and any location is known as “mobile learning”. This type of learning can be seen as an extension of eLearning. Considering the definition of O’Malley one notices that this definition does not exactly match with the idea of the MathCityMap-Project (MCM), because the learning environment in the MCM-Project is predetermined. Combined with the math trail method the project enables mobile learning within math trails with latest technology.In the MCM-Project students experience mathematics at real places and within real situations in out-of-school activities,with help of GPS-enabled smartphones and special math problems. In contrast to the paper versions of math trails we are able to give direct feedback on the solutions by using “mobile devices” such as smartphones or tablets. If the user has difficulties in solving the modeling task, stepped hints can be provided. The teacher is able to use the MCM-Portal to upload tasks developed by himself or by his students and he is also able to build a personal math trail for his students.